Montgomery County, Maryland property tax appeal guide for 2027

Montgomery County real-property assessment appeals are handled through Maryland’s state assessment system, not a separate county assessor. For the 2027 tax year, the regular county-wide Petition for Review deadline is January 4, 2027, and the Maryland date of finality, or valuation date, is January 1, 2027. SDAT explains that owners may appeal a reassessment notice, file a Petition for Review for the next taxable year, or file certain purchase appeals for transfers between January 1 and June 30. Reassessment notice appeals are due within 45 days of the notice date. See SDAT’s Assessment Appeal Process.

Quick facts

Item	Montgomery County 2027 detail
County	Montgomery County, Maryland
County FIPS	24031
Tax year	2027
Date of finality	January 1, 2027
Regular Petition for Review deadline	January 4, 2027
Reassessment notice deadline	45 days from the notice date
First agency	Maryland State Department of Assessments and Taxation (SDAT)
Next appeal body	Montgomery County Property Tax Assessment Appeals Board
Further review	Maryland Tax Court
Baseline rate used for estimates	$1.1032 per $100 of assessed value, or 0.011032

What you are appealing

In Montgomery County, focus on whether the total market value is correct. SDAT advises owners to focus on value-affecting points, worksheet or characteristic errors, and comparable sales that support the value being claimed. A higher percentage increase, a disliked tax bill, local service concerns, or general tax policy objections are not the same as evidence that the assessed market value is wrong. SDAT’s guidance is available on its Assessment Appeal Process page.

The most common value-based reason is that the Total New Market Value does not reflect market value as of January 1, 2027. Other verified reasons include Mathematical errors or inaccurate property characteristics, Classification incorrect, and Events or conditions affecting value since last regular assessment.

Filing steps and official process

1. Read the SDAT notice or decision letter. Use the deadline and instructions stated there.
2. Gather value evidence. Start with comparable sales, the SDAT worksheet, property record details, photos, repair evidence, or a recent appraisal if available.
3. File with SDAT. For the regular 2027 Petition for Review, use the January 4, 2027 deadline. For a reassessment notice, use the 45-day notice deadline.
4. Review SDAT’s decision. If you disagree, follow the decision letter to appeal to the Montgomery County Property Tax Assessment Appeals Board.
5. Prepare again for PTAAB. PTAAB explains that the board hearing is treated as a new hearing, so evidence must be submitted again. PTAAB also states that owners may present the appeal in writing or appear at the hearing. See the PTAAB FAQs.
6. Consider further review only if needed. SDAT and PTAAB materials state that further appeal may be made to the Maryland Tax Court within the applicable 30-day period after the PTAAB order or notification.

For statewide volume context, Maryland’s Property Tax Assessment Appeals Boards reported an appeal count of 8,578 appeals received in calendar year 2024 and estimated 9,500 appeals received for 2026 in the FY2027 Managing for Results report. That statewide volume metric is not a Montgomery County win rate, but it shows that assessment appeals are a regular part of Maryland’s property-tax system. Source: Property Tax Assessment Appeals Boards MFR PDF.

Comparable sales for a 2027 Montgomery County appeal

Maryland does not publish a Montgomery County-specific hard rule for comparable-sale radius, living-area variance, lot-size variance, or maximum number of residential comparable sales. TaxSauce therefore uses conservative screening defaults: up to 5 comparable sales, preferably in the same SDAT neighborhood or a highly similar market area, within 5 miles as an outer screening limit, and as close as possible to the January 1, 2027 valuation date.

For this 2027 policy year, the conservative sale window begins January 1, 2024 and runs through January 1, 2027. Sales nearest the valuation date should usually carry more weight. Good comparable sales are arm’s-length, open-market transfers of properties similar in location, use, physical characteristics, and condition. Avoid family transfers, distressed or forced sales, partial-interest transfers, nonmarket consideration, unusual financing, or limited property-rights transactions unless the difference can be explained or adjusted.

Each comparable should include the address, sale date, sale price, source, and key property characteristics. PTAAB guidance says the best evidence is comparable sales of properties very similar to the owner’s property, close to the property, preferably in the same subdivision or neighborhood, and near the date of finality. PTAAB also says evidence farther from the subject property or different in design, condition, location, quality, construction, size, or age receives less weight. See PTAAB’s FAQs.

Estimating tax impact

Montgomery County’s current baseline real-property tax table includes a common nonmunicipal residential class total rate of $1.1032 per $100 of assessed value, expressed as 0.011032. Actual tax rates can vary by municipality, special district, and tax class, and Montgomery County states that tax rates are set annually by the County Council. Check the County Finance Department’s tax rate tables for the rate that applies to a specific property.

A simple estimate is:

Possible annual tax change = assessment change × applicable tax rate

For example, if the applicable rate were 0.011032 and the taxable assessment were reduced by $50,000, the estimated annual tax difference would be about $551.60 before any property-specific caps, credits, municipal rates, or special district charges. This is an estimate, not a prediction of outcome.

How TaxSauce can help

TaxSauce can help organize a Montgomery County appeal file by checking the assessment record, screening comparable sales, summarizing property differences, estimating tax impact, and preparing owner-review materials. You review the facts, choose the evidence, consent to the filing package, and submit according to SDAT or PTAAB instructions.